speedy



Jan. 24, Q B. SPEEDY VACUUM TUBE GATES AND GATING CIRCUITS 4 Sheets-Sheet l Filed Aug. 30, 1954 4 Sheets-Sheet 2 Jan. 24, 1956 c. B. SPEEDY VACUUM TUBE GATES AND GATING CIRCUITS Filed Aug. 30, 1954 Jan. 24, 1956 Y c. B. SPEEDY VACUUM TUBE GATES AND GATING CIRCUITS 4 Sheets-Sheet 5 Filed Aug. 30, 1954 a .Vl

o oooo oooo o o oo n OOQOOOOOODOT Jan. 24, 1956 c. B. SPEEDY VACUUM TUBE GATES AND GATING CIRCUITS 4 Sheets-Sheet 4 Filed Aug. 30, 1954 I all!!! IIIIII lllllllIIIIIIII IIIIIIII rllllllvllllllll' IIII United States Patent() ce This inventionlrelates to vacuum tube gates and gating circuits.

.In.electronic kdigital .computing and switching systems the Vuseof gating circuits is lfrequently essential vorV desirable. The present invention .is V.based .on the observation that a computing or switching systemneed consist` only of different combinations ,'ofthree f basic elements, these being a bistable element, `agateelement,.and an isolating element or diode. It hasbeenfurther observed that in applying these elements the interconnections .are always bi-stable elements used to control gates, gate `outputs to trigger bi-stable elements, orgate outputs yto other gate inputs. In additiondiodes arenecessary for isolation of-parallel input and ,output elements.

This particular function of bi. stable elements controlling gates is of fundamental'importance digital computing circuits andnormally requires the use of a number of conventional .,gridfcontrolled vacuum .tubes ofrthetype used in radio receivers.

The object of this invention. is. to provide for this function .with a single Vacuum tube ina circuit requiringfew additional components, and which is not subject to critical tolerances -eit-her in component values or input levels.

The `vacuum tube of thisinvention is designed for use -as a bi-stableelement controlling one .or 'twogates Inf two .gatesare providedrt'he preferred arrangement is one in which they are controlled .by the bifstableelement so that when one gate isopenfthe'o'ther is closed, and vice Versa. The vacuum tube .hasthe additionaladvantage .thatthe .varionscontrol and Output electrodes may be operated at the samenormalD. C. llevelallowing direct interconnection between input electrodes .and gate Aoutputs.

According to this invention `an electron beam vacuum tubefgate device comprises meansforgenerating-an elecbeam into two sections; abi-stable elementincluding the electrode cross-connected tdafrstpairof de ectingelectrodes, Asaid first pair of deecting electro'desalso` operat- 'ingto delect the second fsectionof'the electronbeam, a second-pairof deeeting-electrodes forthe said iirstsec- .tion of the pelectron beam, means for Iapplying control signals 1 to said second pair .of deilecting electrodes 4.where- Yby to shift-the electron beamfrom oneestable-staterwhere it :falls .ontone ,parrot the divided` target tothe other stable, state where ity falls onthe-.other partofthe divided target; a .gating element yincluding,there.secondsection .of

electron beam, the saidA first pair. ,of `detlezctin-g.Aelectrodes, va divided vtarg'etYelefrodeV for the said second section .of the,electron`beam,an`d a further pair of dellecting electrodes for the said,V seccnd section of the velectronbeam, the -divisionbetweentheparts of the lastmentioned target electrode andthepotentialsjapplied to the deecting electrodes being such that in the :absence of signals Aappliedftothe 5 said"ifurtljrer pai'rfof deflecting Yelectrodesfthe said secondportionfof'the electronibearn falls on fthe same part ofI Athetargeteleetrodeiinboth-of rst section ofthe electron "beam and a divided target i 2,732,516 'Patented Jal 24 .195:6

its stable positions, and means'for applying gating signals Yto the said further deecting electrodes whereby when the electron beam is in onestable state the gatingsignals transfer the said second section of the electron beam from the aforesaid same part ofthe target electrode vfor the gating .element to the otherpart but when the electron beam is in the other stablestate the gating signals do not so transfer the .said second section `of the electron beam.

From another aspect an electron beam vacuum tube gate device according to this invention comprises means for generating an electron beam, means for effectively dividing the electron beam into two sections, a rstpair of deflecting electrodes associated with Vboth sections of the electron beam, a second pair of deflecting electrodes associated with the lirst Section of the electronbeam, a target for the rst section of the electronv beam divided Vinto two parts so that when all detlecting electrodes are at the same potentiallthe said-first section dividesapproximately equally between the said parts, resistances between the target kparts and a high tension source, cross- .connections between the said target parts and the said lirst pair of deecting electrodes such that a target part on one side of the electron bearnin its undeected state .is connected to the deecting electrodeof the said first pair on the opposite side, means for applying control signals to the said second pair of deflecting electrodes, whereby to provide a bistable element, a third pair of deecting electrodes associated with the said second section ofthe electron beam, a target electrode for the n second section of -the electron beam divided into two parts such Vthat when `the bi-stable section is in Vone stable state the said second section .of the electron beam .falls on one part adjacent the division between the two parts and when the bi-stable section is inthe Yother stable state the said second section of theelectron beam falls on the said one part well away from the said last-mentioned division, means for applying gating signals to the said third pair of deecting electrodes to deflect the .said second section of the electron beam toward the second part of the last-mentioned targetelectrode, and means for deriving an output from the said last-mentioned second part. Y,

From yet another aspect an electronbeam Vvacuum tube forv use in gating circuits comprises an electron gun for generating a rectangular electron beam, means adapted etectively to divide the electron beam into two sections, a rst pair of deecting electrodes extending substantially the full length of the electron beam, a second pair of deflecting electrodes above the said dividing means, a first target electrode above the said dividing means which is divided into two parts by a centrally disposed division parallel tothe longer dimension of the electron gun, a third pair ofdeflecting electrodes below the said dividing means, and a second target electrode below the said dividing means which is divided into two parts by a division which is parallel to, but oi-set with relation to the division lin theftirst-rnentioned target electrode.

Reference will now be made to the accompanying drawings in which:

Figure l is aperspective view of ak gating vacuum tube according to this invention which includes a bi-stable element and two gating elements;

`Figure .2.is a schematic circuit'diagram of the connec- V tionsof thetube shown; in Figure l;

Figure 3 is an elevation of the target electrode arrangement inthe tube of Figure l;

Figure 4 is a perspective view of a modified vacuum tube according to this invention including a single gating element only; and

Figure 5 is a schematic Vcircuit diagram of the connections of the tube shown in Figure 4.

:'Figure lshows the genera1" `arrangement of "electrodes ing electrodes 15, 16 with the third or lower beam 1Q.l

A fourth pair of deflecting electrodes 17, 1S isy provided which affects all electron beams 8, 9, 10. Screen and suppressor grids 19, 2i) are provided.

Each beam S, 9, is provided with an output target I which is divided longitudinally (i. e. in the same direction 'as the length of the electron beam) into two parts. One

of the target electrodes, in this case the first or upper target, is divided centrally into the parts 21, 22. The division of the other two targets is oliset with respect to kthat of target parts 21, 22. The division of the second target into the parts 23, 24 falls on one side of the division of the irst target and the division of the third target into the parts 25, 26 falls on the other side'of the division of the first target. With no deflecting voltages applied to any of the deliecting electrodes 11 to 13 the upper beam 8 divides substantially equally between target parts 21, 22 while beam 9 falls wholly on target part 23 and beam 1i) falls wholly on target part 26.

A circuit arrangement for the tube is shown in Figure 2. For convenience in drawing, the cathode and anode parts, and also deflecting electrodes`17, 18 have been triplicated, but in the actual tubeathey are each 4 constituted by a single electrode. The target parts 21, 22 are returned to a bus line 27 held at, say, 200 volts positive with respect to the cathode by way of resistances 28, 29, target parts 23, 26 are returned direct to the bus line 27, and target parts 24, 25 are returned to the bus line 27 by way of resistances 30, 31. Target part 21 is cross-connected to deliecting electrode 18 and target part 22 is cross-connected to deflecting electrode 17. Deflect- Ving electrodes 14 and 15 are returned to the bus line 27. vControl signals may be applied to electrodes 11 and 12 at terminals 32, 33 respectively. A first signal to be gated may be applied to deliecting elcterode 13 at terminals 34, and a second signal to be gated may be applied to dellecting electrode 16 at terminals 35.

The upper section of the tube including deflecting electrodes 11, 12 is the bi-stable element or section. Assume that the electron beam 8 falls wholly on target part 22. Then, due to the voltage drop across resistance 29, the potential of deflecting electrode 17 drops and holds the beam on target part 22. Conversely if the electron beam falls wholly on target part 21 it is held there by the voltage drop across resistance 28 applied to deflecting electrode 18. The electron beam 8 can be set to fall wholly on either of target parts 21, 22 by momentarily dropping the potential of deilecting electrodes 12, 11 respectively.

In the absence of signals to be gated applied to deflecting electrodes 13, 16 the electron beams 9, 10 are deiiected similarly to electron beam 8. The division of targets 23, 24 and 25, 26, and the geometry of the tube is chosen so that beams 9, 10 in the gate sections lie just off one or other output target part 24, 25 in eachl state. Thus in the state shown in Figure 2`where the electron beam 8- occupies the position lettered A and falls wholly on target part 22, the electron beam 9 falls onthe target part 23 adjacent the division between it and target part 24, but the beam 10 falls on target part 26 some distance from the division between it and target part 25: in the state where the beam 8 falls wholly on target part 21, shown by the dash line D, the beam 10 falls on target part 26 adjacent the division, whereas beam 9 falls on target part 23 at a point remote from its division.

Assume that, in the absence of signals applied to the 4 terminals 34, 35 (which are therefore held at 200 v. positive with respect to the cathode), the electron beams have been brought to the position A by momentarily dropping the potential of deiiecting electrode 11 by a control signal applied to terminals 32. If now a negative signal to be gated is applied to terminals 34 the electron beam 9 is deflected toward and onto the target part 24 to say the position B and an output signal appears at terminals 36. If a negative signal is applied to terminals 35, however, although the electron beam 10 is moved toward the target part 25, say to the position C, the movement is not sutiicient to carry the electron beam oli the target part 26 and onto the target part 25, so that no output signal appears at terminals 37. Thus the gate section associated with the electron beam 9 is open, but the gate section associated with beam 10 is closed. If however a control signal is now applied to terminals 33 the electron beams assume the positions D, as previously described, and negative signals applied to terminals 34, 35 will then move the beam to positions E and F respectively, so that an output signal will appear at terminals 37 but not at terminals 36. Thus when one gate section is open the other is closed, and control over which gate is open is exercised by control signals applied to terminals 32, 33 associated with the upper or iirst electron beam 8.

While the leads to the target parts 23, 26 may be brought out separately, they may be connected internally, and a suitable target electrode construction in such a case is shown in planV in Figure 3. Glass beads supporting the electrodes are shown at 38. The scale is ive times full size for a particular tube.

In the vacuum tube just described the bi-stable element is used to control two gates so that when one gate is open the other is closed, and vice versa. However for some applications only one gate is required, and in such cases one gate section, for example the lowermost or third section, may be omitted. Furthermore the deiiecting electrodes 17, 18 which are common to the bi-stable section and the gate section or sections may be the irst in order from the cathode, and not second as in Figures 1 and 2.

A modified vacuum tube consisting of a bi-stable section and a single gate section only is shown in Figure 4. An electron gun consisting of a cathode 41, cathode shield 42 and anode 43 produces a ribbon type electron beam. The electron vbeam passes through a first pair of deflecting electrodes 44, 45, which act on the whole length of the electron beam, and then through a second or upper pair of deiiecting electrodes 46, 47 and a third or lower pair of deiiecting electrodes 48, 49, of which only 49 is visible in Figure l. The pairs of defiecting electrodes 46, 47 and 48, 49 are similar and are similarly placed with respect to the electron beam with one pair above and longitudinally spaced from the other: these pairs of deiiecting electrodes act independently on their sections of the electron beam. The electron beam then passes through a screen grid 50 and a suppressor grid 51. The electron beam is divided into a iirst or upper section and a second or lower section by a solid strip 52 across the suppressor grid. The width of this strip is chosen with respect to the spacings between the pairs of deliectors to provide sutiicient isolation between the sections. A divided target electrode consisting of target parts 53, 54 is provided for the first or upper section of the electron beam, and a second divided target electrode consisting of target parts 55, 56 of which only 56 is visible in Figure 1, is provided for the second or lower section of the electron beam. The target electrodes are ldivided longitudinally. The division in the lower section is centrally placed, and that in the upper section is offset, so that with all deflectors at the same potential the lower section of the beam divides substantially equally between the target parts 5S, 56, and the upper section falls wholly on target part 53.

A circuit diagram of the tube with a single gate section is shown in Figure 5. The operation of this tube will be obviousfrom the description given with respect to Figures l and 2.

What lis claimed is:

1. An .electron beam` vacuum tube gate ydevice comprising meansfor generating Van electron beam, means for effectively dividing the electronbeam into two sections; a bi-stable element'tinclu'ding the first .section of the electron beam and a divided target electrode cross-connected to a rstpair of deecting electrodes, said first `pair of delecting electrodes also Operating to deflect the second section of the electron'.beama second pair of deflecting electrodes `fonthe said first. section tof the .electron beam, means for applying control signals tosaidlsecond pair of deecting electrodes whereby to shift the electron beam from one stable state'whereiit vfalls on one part of the divided targetzto the Yotherlstable state wherefit falls Von the other part of (the fdivideditarget; 'a gating element includingrthe said secondsection of theelectron beam, theA said first pair` of deflecting electrodes, Va divided target electrode for the saidsecond section of the electron beam, and a further pair? of .deflecting electrodes for the said second section of the electrontbeam, the division between the parts of the last-mentioned targetelectrode and the potentials applied to the deflecting electrodes being such that inthe absence of signals-applied to the said further pair of deflecting Velectrodes-the said second section of the electron beam falls on the same part'of the target electrode in both of its stable positions, and means for applying gating signals to the'said further deflecting electrodes whereby when-the electron beam is in one stable state the gating signals transfer-*the said second section of the electron beam `from the aforesaid .same part of the target electrode for the gating element to the other part but when the electron beam is` Vin the other stable state the'gating signals dofnot so transfer the said second section ofthe electron beam.

2. An electron beam vacuum tubefgate device comprising means for generating an electron beam, means for effectively dividing the electron beam into two sections, a first pair of deilec'ting electrodes associated with both sections of the electron beam, a second pair of deflecting electrodes associated with the first section of the electron beam, a target for the first section of the electron beam divided into two Vparts so that whenA all deflecting electrodes areat 4the same'potential the said first section divides approximately `equallybetweenthe said parts, resistances between the target parts and a high tension source, cross-'Campagnes between the Said target parts and the said'firs't pair of defiecting electrodes such that a target part on one side of the electron beam in its undeflected state is connected to the deflecting electrode of the said rst pair on the opposite side, meansfor applying control signals to the said second pair of detiecting electrodes, whereby to provide a bi-stable element, a third pair of deilecting electrodes associated with the said second section of the electron beam, a target electrode for the second section of the electron beam divided into two parts such that when the bi-stable element is in one stable state the said second section of the electron beam falls on one part adjacent the division between the two parts and when the bi-stable element is in the other stable state the said second section of the electron beam falls on the said one part Well away from the last-mentioned division, means for applying gating signals to the said third pair of deflecting electrodes to deflect the said second section of the electron beam toward the second part of the last-inentioned target electrode, and-means for deriving an output from the last-mentioned second part of the target electrode for the second electron beam.

3. An electron beam Vacuum tube gate device as claimed in claim 2 and including an electron gun for producing a ribbon type electron beam, a suppressor grid between the last of the defiecting electrodes and the target electrodes, and solid strips or plates secured to the suppressor grid to divide the electron beam into two sections.

4. An Aelectron beam 4vacuum tube ,gate device .com prising means for v,generating an electron beam,.means for efiectivelydividing` the .electron beam into ,three sections; a bi-stable element including a first section of the electron beam `and a vdivided target electrode crossconnected to a first pair of deflecting electrodes, said first pair of deflecting-v-electrodes also operating Yto deect the second and third sections of the electron beam, a second pair of deflecting electrodes for the said first section of the electron beam, means for applying control signals to said second pair of deecting .electrodes whereby to shift the `electron beam from one stable state where it falls on one part of the divided target-to the other stable'state where it falls on the other ,part of the divided target; a firstgating element including the second section of the electron beam, the said first pair of deflecting electrodes, a'divder target electrode for the said second section of the electron beam, and a further pair of deflectingielectrodes for the said second section ofthe electron beam, the division between the parts of the last-mentioned target electrode and the potentials applied to the deflecting electrodes' being such that in the absence of signals applied to the said further pair of deilecting electrodes the said second section-of the electron beam falls on the same part of the target electrode. inboth of its stable positions, and means for applying gating signals to said further deflecting electrodes whereby when the electron beam is in one stable state the gating signals transfer the said second section of the electron beam from the aforesaid same part of the target electrode for the first gating element to 4the other part but when the electron beam is in the other stable state the gating'signals do not so trans fer the said second section of the electron beam; and a second gating elementincluding the third section of the electron beam, the said first pair of deflecting electrodes, a divided ktarget electrode for the said third sec-V tion of the electron'beam, and a further pair of deecting electrodes for the said third section of the electron beam, the division between the parts of the lastmentioned target .electrode and the potentials applied to thev deecting electrodes being such that in the absence of signals applied to the last-mentioned further pair of deecting electrodes the said third section of the electron'beam falls on the same part of the target electrode therefore in both of its stable positions, and means for applying gating signals to said last-mentioned further deflecting electrodes whereby when the electron beam is in the aforesaid other stable state the gating signals transfer the said third section of the electron beam from the last-mentioned same part of the target electrode for the second gating element to the other part but when the electron beam is in the aforesaid one stable state the gating signals do not so transfer the said third section of the electron beam.

5. An electron beam vacuum tube gate device comprising means for generating an electron beam, means for effectively dividing the electron beam into three sections, a first pair of deecting electrodes associated with all sections of the electron beam, a second pair of defleeting electrodes associated with the first section of the electron beam, a target for the first section of the electron beam divided into two parts so that when all deflecting electrodes are at the same potential the said first section divides approximately equally between the said parts, resistances between-the target parts and a high tension source, cross-connections between the target parts and the said first pair of deflecting electrodes such that a target part on one side of the electron beam in its undeflected state is connected to the defiecting electrode of the said first pair on the opposite side, means for applying control signals to the said second pair of deflecting electrodes, whereby to provide a bistable element; a third pair of deflecting electrodes associated with the said second section of the electron 7 beam, a target electrode for the second section of the electron beam divided into two parts such that when the bi-stable element is in one stable state the said second section of the electron beam falls on one part adjacent the division between the two parts and when the bi-stable element is in the other stable state the said second section of the electron beam falls on the said one part well away from the last-mentioned division, means for applying gating signals to the said third pair of dellecting electrodes to dellect the said second section of the electron beam toward the second part of the last-mentioned target-electrode; a fourth pair of deecting electrodes associated with the said third section of the electron beam, a target electrode for the third section of the electron beam divided into two parts such 4that when the bi-stable element is in the said other stable state the said third section of the electron beam falls on one lpart adjacent the division between the two parts and when the bi-stable element is in the said one stable state the said third section of the electron beam falls on the last-mentioned one part well away from the last-mentioned division, means for applying gating signals to the said fourth pair of devtlecting electrodes to deect the said third section of the electron beam toward the second part of the last-mentioned target electrode; and means for deriving outputs from the target electrodes for the second and third sections of the electron beam.

6. An electron beam vacuum tube gate device as claimed in claim 5 including an electron gun for producing a ribbon type electron beam, the anode of the electron gun being pierced with rectangular openings to divide the electron beam into three sections, the divisions between the parts of the target electrodes being parallel to the longer dimensions of the electron beam.

7. An electron beam vacuumV tube gate device as claimed in claim 6 wherein the division between the parts of the target electrode for the first section of the electron beam is substantially central, the division between the parts of the target electrode for the second section is oit-set to one side of that for the rst section, and the division between the parts of the target electrode for the third section is oit-set to the other side of that for the rst section.

8. An electron beam vacuum tube for use in gating circuits comprising an electron gun for generating a rectangular electron beam, means adapted eiectively to divide the electron beam into two sections, a rst pair Vof deflecting el-etcrodes extending substantially the full length of the electron beam, a second pair of deecting electrodes above the said dividing means, a Vfirst target electrode above the said dividing means which is divided into two parts by a centrally disposed division'parallel to the longer dimensions of the electron gun, a third pair of deflecting electrodes below the said dividing means, and a second target electrode below the said dividing means which Vis divided into two parts by a division which is parallel to but off-set vwith relation to the division in the first-mentioned target electrode.

9. An electron beam vacuum tube for use in gating circuits comprising an electron gun for generating a rectangular electron beam, means adapted effectively to divide the electron beam into three sections, a first pair of dei'lecting electrodes extending substantially the full -length of the electron beam, a second pair of deecting electrodes for the first section of the electron lbeam only, a rst target electrode for the rst section of the electron beam which is divided into two parts by a centrally disposed Vdivision parallel to the longer dimension of the electron beam, a'third pair of deflecting electrodes for the secondjsection of the electron beam only, a second target electrode for the second section of the electron beam which is divided into two parts by a division which is parallel to but off-set with relation to the division in the rst-mentioned target electrode, a fourth pair of detlecting electrodes for the third section of the electron beam only, a third target electrode for the third section of the electron beam which is divided into two parts by a division which is parallel to the division in the first-mentioned target electrode but offset with relation thereto on the opposite side to that of the said second target electrode.

Y l0. A gating circuit including a vacuum tube as claimed in claim 8 in which the parts of the target elec- References Cited in the file of this patent UNITED STATES PATENTS Selgin a June 7, 1949 Adler ..V Oct. 21, 1952 

